If you are sure the bulb is good then try this. Unplug the opener and remove the light bulb. Use something small to pull out on the center contact in the light socket.

At least some fluorescent bulbs don't work properly in some Craftsman openers, in my experience. If you are using a fluorescent, that might be the problem.

Lite goes on fine but after a second or two, there is a click from the opener (like a relay opening) and it goes out. Supposed to stay on for a few minutes before it "clicks" off. I don't see anything to adjust to increase the time delay but hope there is something. Any ideas?

Perhaps you are overloading the the opener's lamp circuit. Are the bulbs both within the opener's rated wattage?

Other than that, all I can think of is a defective logic board.